LOL has a certain quirkiness to it, even phonetical lol is a pleasant little word, unobtrusive if you know what I mean.
LPH just sounds too far, I feel the urge to punch anyone using that term already. People who laugh pretty hard all the time are morons, at least if you give a little chuckle, you can say LOL with a straight face. LPH just spells out bandwagon-moron.
If this is the game they want to play, then I call...
LSHTALPOPPO
''Laughing so hard that a little piece of poop popped out.
LLAFJHAOWINTF
''Laughing like a frisbee just hit an old woman in the face.''